Generally, brake backing plates for mounting and supporting drum brake components are well known in the art. Typically known arrangements provide a unitary backing plate with an axle receiving opening for axially mounting the plate onto the axle housing support flange of a vehicle. Once the brake components, all commonly known in the art, are positioned and mounted, these typical backing plates may only be replaced by labour intensive disassembly of the rear wheel components of the vehicle, including removal of the axle shaft. Removal of the damaged backing plate from the axle support flange is accomplished by means of unbolting, or other methods well known in the art, but regardless of the precise technique used the axle shaft must still be removed in order to install the replacement unitary brake backing plate.
The known prior art reflects the above mentioned unitary brake backing plates. Common examples of unitary plates are those manufactured as described in the Mathues U.S. Pat. No. 4,061,429, as a single or one-piece circular brake plate, (resembling a large washer), the centre hole being the axle receiving opening. Another example is that shown in the Dubuc U.S. Pat. No. 3,576,237, that is manufactured as described in the patent, as having an inner member and two outer allochiral portions (mirror images) that are assembled by welding the three pieces together, or employing one of numerous other conventional fastening techniques, therefore effectively providing a one-piece or unitary brake backing plate at the manufacturer's level. Regardless of the allochiral outer members, the inner member fully encloses the axle receiving opening, thereby necessitating the removal of the vehicle axle shaft for purpose of replacement of the brake backing plate.
Generally speaking, both of the prior Mathues and Dubuc backing plates discussed herein can only be axially mounted onto the axle housing support flange of a vehicle after the axle shaft has been removed.
Other background patent documents which illustrate the prior art techniques include Canadian patents 1,075,176; 1,080,138; 651,363; 1,105,856; and U.S. Pat. Nos. 3,548,976; 4,337,851; 4,452,347; 3,279,568; and 3,216,532.
Although the patent references described and noted above relate to brake supporting structures, none discloses a brake backing assembly which facilitates radial replacement onto the axle housing support flange of a vehicle while the axle shaft is in situ.
Accordingly, there is a distinct need for a brake backing assembly which facilitates rapid replacement onto a vehicle without the disadvantage of having to extensively disassemble the components of a rear wheel including removal of the axle shaft. Having regard to this need, the present invention satisfies the same by providing a novel brake backing assembly which may be radially replaced as hereafter described thus obviating the extensive disassembly inherent with the prior art arrangements.